Dipper mounting



Feb. 24, 1925. 1,527,813

A. K. MITCHELL DIPPER MOUNTING Filed Novsfi. 1-921 2 Sheets-Sheet 1 ATTOR EY INVENTOR A. K. MITCHELL mrrnn xoun'rme Filed'uov; a, 1921- Feb. 24, 1925.

ATTORNEY Patented Feb. 24, 1925.

UNITED STATES 1,527,813 PATENT OFFICE.

ARTHUR K. MITCHELL, .OF BRONXVILLE, NEW YORK, ASSIGNORTO ST. JOSEPH LEAD COMPANY, on NEW YORK, N. Y.,

A CORPORATION OF NEW -Y0RK.

DIPPER MOUNTING.

Application filed iblovember 3, 1921. Serial 110,512,413.

To all whom it may concern:

Be it known that I, ARTHUR K. MITCHELL, a citizen of the United States, and resident of Bronxville, countyofWestchester, and State of New York, have invented certain new and useful Improvements in Dipper as are employed in underground mining whereby the filling of the dipper with the ore is facilitated in the forward thrust movement of the dipper and liability of breaking the boom operating connections or other parts is reduced to a minimum- In carrying out my present invention, in one embodiment thereof, I propose to mount the dipper on a. swinging and traveling boom by suitable means which permits of a yieldingly resisted longitudinal movement with a simultaneous transverse oscillation of the dipper in its forward thrust.

This produces the equivalent of a worming action so that the dipper teeth will ,readily bite into the pile of ore, facilitating the collection of the ore within the dipper and relieving the dipper teeth of excessive strains. It is a further object of the invention to provide an improved dipper mounting as above characterized which is of simple construction, of maximum stability, reliable and efficient for the purpose in'view and adaptable for use in connection with various forms ofdippers or shovels. 7

With the above and other objects in view, the invention consists in the improved dipper mounting to be hereinafter more particularly described and in the form, construction and arrangement of the several parts illustrated in the accompanying drawings and subsequently incorporated in the subjoined claims.

In the drawings wherein Ihave illustrat ed one practical and satisfactory embodiment of the invention and in which similar reference characters designate correspending parts throughout the severalforward ends of the boom arms and the connecting head therebetween with the dipper or shovel mounted upon said head;

Figure 2 is a central longitudinal section taken on the line 2+2 of Figure 1;

Figure 3 is a section taken on the line 3-3 of Figure l; and

Figure 4 is a front end elevation illustrating in dotted lines the transverse swinging. movement of the dipper. I

The invention constituting the subject matter of the present application is particularly designed for use in connection with an underground mining machine of the type disclosed in my Patent 1,501,795, issued July 15, 1924, though it'is to be understood that in so far as my present disclosures are concerned, they are not neces sarily limitedin their utility to application and use in connection with such a machine but can be employed generally upon mining or excavating machines of the various types now in general use.

In the machine of my patent above re- {erred to, apair of longitudinally traveling, vertically swinging boom arms are supported upon a turn table.- In the accompanying drawings, theforward ends of the boom arms 5 are rigidly connected to each I other by means of a head 6. The means whereby th s head is connected to the boom arms constitutes no essential part of the present invention, but it may be stated that in the end of each of the arms 5 a member 7 is inserted and securely welded to the arm. Each ofthese members has a forwardly extending tapering portion 8. The head 6 comprises a central portion 9 from opposite sides of which tubular arms extend at an oblique inclination and in a rear ward direction, each of the arms terminat ing in a hub 10 having a tapering here to receive the part 8 of one of the members 7. The parts 8 and 10 are suitably keyed together and the members 7 terminate at their forward ends in threaded ex.- tensions to receive the nuts 11 which are adjusted into tight bearing contact against the hubs ,10 and are then pinned or other wise fixed in their adjusted positions.

The center portion 9 of the boom head is provided with a longitudinally extending chamber 12 closed-at its rear end and opening at its other end through the front side of the head. The dipper or shovel 13 is suspended from the boom head but instead of rigidly fixing this dipper in position, it is mounted for a ho ily longitudinal movement as well as a transverse oscillating movement with respect to the boom head. The specificform or construction of the dipper is not of importance, though I preferably use-a dipper .which is similar in many respects to that disclosed in Patent 1,418,321, issued June 6, 1922. For the purpose of the present explanation it will sufiice to state that the rear wall of the dipper 13 is provided with a. part 14 extending upwardly above the upper edges of theside walls of the dipper and positioned at the rear 'side of the chambered central part 9 of the'boom head.

Within the outer end of the chamber 12 r a piston 15 is snugly fitted for reciprocating-movement, said piston having a 'stem or rod 16 of reduced diameter which is loosely engaged through an opening 17 in the'rear wall of said chamber. lhe end portion of the piston stem is again reduced in diameter and projects rearwardly through an opening 18 in the upward extension 14 on the rear wall of the dipper. A nut 20 threaded upon the end of the piston stem tightly clamps theextension 14 against the shoulder formed by the inner end of the reduced portion ofithe piston stem 16 and is pinned or otherwise securely locked against rotation. Within the" chamberl2 of the boom head and surrounding the piston head 16 a coil. spring 19 is arranged and bears at its for-. ward end against the piston '15 and at its rear end against the wall of said chamber.

Theouter end f the-piston15 forwardly of" the boom head is formed with a transversely extending bail bar- 20, theends of which are downwardly turned and rivbodv as at 20.

eted to the opposite side walls of the dipper These side walls adjacent to the rearwall of the di per are provided in' t heir upper-"edges with the concave re- -fces se s- 21' which accommodate the tubular portions ofthe boom head in the transverse rocking or oscillating" motion of the dipper.

' It will thus be seen thatth'e dipper is rigidly I yielding] connected to the front and rear ends-of thev piston and that the dipper is normally held in a forwardly roje cted posi tion wit relation to the Boom head by means of the spring 19. I also'preferably provide means for yieldingly resisting a transverse rocking or oscillating movement of the piston and the di per with respect to the boom head. As erein shown, this means may consist of a leaf spring 22 havmg one or more laminations, the medial port on of th1s spring being securely fixed upon the forward end of the medial portion 9 of the boom head and the ends of the spring bearing upon the bail bar 20 at opposite sides of the piston. However, this arrangelongitudinally and rearwardly'with respect to the boom head and the spring 19 will be laced under compression and will yieldlngly limit such movement. Should the dipper teeth on one side ofthe center of the thrusting movement, the dipper will move dipper encounter a large mass of ore, the

dipper will rockor tilt transversely as shown in dotted lines in Figure 4, against the action of the spring 22 or other yieldable resistance so that the teeth will be positioned below the ore mass. This rocking or oscillating movement together with the yielding rearwardmovement of the dipper produces the equivalentof a worming action as in-the manual-use of a shovel and greatlyfacilitates the gatherin or collection of the ore into the d pper. lso the possibility of the dipper belng broken off, mutilated or distorted, is substantially obviated. reducing the necessity for repairs. and the, expense incident thereto to a minimum. It is of course understood that upon overcoming the momentary resistance to' the 'forward thrust of the dipper into the mass of the ore, the spring 19 immediately acts to again project the dipper forwardly upon the boom head to its normal position. This spring may thus function-repeatedly durin each thrusting movement of the dipper. 1 said springv is entirely housed within the chamber 12, the, ore or other material candrawings, the construction, mannerof oper- A ation and several advantages of 111 improved di per mounting will be clear y and fully un erstood. The invention as herein disclosed simple and compact in its arrangement, reliable and efiicient in operation and will not add materially to the production cost of mining or excavatin machines as shown in my prior application or heretoforein general use. 1

While I have herein shown and described one satisfactory and practical embodiment of the invention, it is' nevertheless to be understood that the improved dipper mountin might also be exemplified in numerous ot er alternative constructions and I accordingly reserve the privilege of adopting its the Y all such legitimate changes as may be fairly embodied Within the spirit and scope of the invention as claimed.

' hold said dipper in its normal position.

3. The combination with a boom having a chambered head, a piston working in said chamber, a dipper suspended from said piston beneath the boom head, and a spring arranged in said chamber coacting with the piston to yieldingly resist rearward movement of the dipper and piston relative to the boom head in the forward loading thrust of the dipper.

4. In combination with a boom, a dipper,

means supporting the dipper from the boom and permitting of a transverse oscillating movement of the dipper with respect to the boom in the forward thrust of the dipper,

and means mounted on the boom and co acting with said su porting means to resist such oscillation of t e dipper and for yieldj ingly holding the same in a normal position with relation to the boom.

5. In combination with a boom, a dipper, a piston mounted upon the boom to reciprocate longitudinally thereof and fixed at its opposite ends to the dipper, and a spring coacting with the iston to project the dipper forwardl of the boom and yieldingly hold said ipper in a normal position.

6. In combination with a boom, a dipper, a piston fixed to the dipper and mounted upon the boom for reciprocation longitudinally thereof and for axial oscillation, a spring coacting with the piston to yieldingly resist a rearward longitudinal movement of the dipper and piston in the forward thrust of the dipper, and additional means for yieldingly resisting the oscillation of the dipper and the piston with. respect to the boom. 7

7. In combination with a boom, having spaced arms and a head connecting sai arms, a dipper, a piston mounted in said head for reciprocation longitudinally of the boom and fixed at its opposite ends to the dipper, and a spring mounted in the boom head and coacting with the piston to yieldingly resist the rearward movement of the dipper and the piston in the forward thrustofthe dipper.

8. In combination with a boom having spaced arms and a head connectin the same, said head having-a chamber, a dipper, a piston mounted to reciprocate and oscillate in said chamber and connected to the dipper, a spring arranged in said chamber coacting with the piston to yieldingly resist a rearward movement of the dipper and the piston in the forward thrust of the dipper and additional means yieldingly resisting the oscillating movement of the piston and the dipper with respect to the boom head.

In testimony that I claim the foregoing as my invention, I have signed my name hereunder.

ARTHUR K. MITCHELL. 

